states remains united in the effort to stop terrorism. vice president joe biden at aer is nobodyny in sanction -- ceremony in shanksville, pennsylvania. the united airlines flight crashed after passengers struggled with the hijackers who had planned to crash that flight into the u.s. capitol building. president obama and governor romney are pulling their negative ads on this solemn day, and while both candidates are putting aside politics for the moment, a new poll shows the president ticking upwards among registered voters. he is six points ahead, 50-44. but among likely voters, the two are in a virtual dead heat with president obama at 49%, governor romney at 48%. larry sabato is director of the center for politics at the university of virginia. larry, a lot of experts are saying that this is going to be a base election where the bases get excited and support their candidate in one way or another. this poll would seem to indicate that president obama's base got very excited by the democratic national convention. his support boomed among